you burn about the same number of calories speed walking (about 5 mph) as you do running if you go the same distance.
I think only someone who is extremely tall or has a really long stride would be able to walk at 5mph, most average people are jogging/running at this point, hence why the calorie burn would be the same.
There are many many benifits to running, but the bottom line is if it hurts you then you shouldn't be doing it. That's not to say you can never be a runner. I walked off many of my lbs and didn't start running until I was in the 180s, so just keep walking and see how it goes.
268 lbs - Journey Begins (January 11, 2006)
197 lbs - 71 lbs lost (October 15, 2007)
247 lbs - 50 lbs gained pregnancy (August 22, 2008)
195 lbs - baby weight gone (July 7, 2009)
168 lbs - 100 lbs lost (March 26, 2010)
148 lbs - GOAL! 120 lbs lost (July 18, 2010)
138 lbs - 10 lbs under goal (December 29, 2010)
PR 1/2 Marathon - Time 1:59:50 (November 11, 2012)
PR Marathon - Time 4:40:53 (March 18, 2012)
Today 140s & training for my Health
"There is nothing you can't have tomorrow so there is no reason to eat it all today."